MacroSystem Bluebox World - Manual (Page 31)

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Appendix A
The construction of a Bluebox wall
To make effective use of the Bluebox effect,
you most often require a Bluebox wall in front
of which you can film persons or objects. The
requirements of such a Bluebox wall in the film
and video world are consistent; Casablanca is
no exception to this rule. So if you have a well-
constructed Bluebox wall - perhaps from the
days of linear video editing - you can continue to
use this without difficulty. Below are a few tips
for all those users who must first construct such
a wall.
A.1 Placement
A Bluebox wall must be large enough. If you
wish to record a person filling almost the entire
screen (in the style of a newsreader) then a
small piece of fabric stretched behind the desk
will be sufficient. If, on the other hand, you want
the person to move large distances to the side,
then you need a very large room decorated
entirely in blue (a“virtual studio“). The rooms
in which you have to work will often therefore
set limits to your Bluebox wall. The room under
consideration should be sealed against daylight
(because it is uncontrollable).
A.2 Coloring the room blue
There are basically two ways to create a simple
Bluebox environment: blue paint, or hanging
blue cloth around the room.
Why blue? In principle, any other color (such
as green or red) might be considered. Blue,
however, along with green, has been found over
70 years of practice to be the most suitable,
because pure blue is rarely found in nature.
It is often people who represent the object
- human skin has almost no blue, but does have
many red components. Red would therefore
be quite unsuitable. Painting is easy, and (on
flat walls) very even. The effects of fabric folds
are unknown here. Painting is, however, also
relatively permanent. Many practitioners would
be subject to their partner‘s veto if the living
room were to be painted blue...
Hanging up a blue cloth has many advantages.
Cloths are easy to remove, can be flexibly po-
sitioned, and are easily packed away. But there
are problems, too. Cloths easily become folded,
and folds in turn throw shadows. Blue cloth
can be bought by the metre in fabric stores, but
bedsheets and the like are also suitable. Buy
a little more than you actually need - then you
have some reserve. Such cloths can be fastened
with, for instance, adhesive tape (double-sided),
drawing pins (to plasterboard walls) or hooks.
Mount your cloth tautly, without folds! Do not
use a blue that is too saturated or intense - a
relatively light blue is better.
A.3 Illumination
Illumination is the biggest problem with Bluebox
work. Even the best Bluebox environment will
yield poor results if it is unevenly lit. You need a
few powerful lamps for lighting. From the point
of view of the camera, the whole of the blue
environment should look nicely bright and even!
The object itself, or person, must also be well
illuminated. A number of spots should therefore
always be directed at the object.
The edges, (against the blue background),
should be sharp and bright. But this must never
cause the shadows to fall strongly on the blue
wall! Inclined illumination from above is most
appropriate here. The lighting for the blue
background should be located in such a way that
the object will not later obscure the light.
A.4 Camera placement
The camera cannot move as freely within the
Bluebox room as it can otherwise. Usually the
room is only partially blue, and the camera must
always work while pointing at this area. Every
camera position (and also every zoom setting!)
must therefore be considered very carefully.
Placing the camera on a tripod is strongly
recommended.
We now wish you a lot of fun as you create
some trick sequences!
The old rules also apply to Bluebox work:
practice makes perfect, and there is no substitu-
te for experience.